Abstract：The development of multivalent batteries is promising for resolving lithium batteries' bottlenecks, such as safety issue, high cost and limited energy density. Calcium (Ca) is more abundant, and has lower standard reduction potential (-2.87 V) and density than zinc and magnesium. However, Ca-based battery gets less attention than other multivalent batteries, which is mainly due to the limitation of Ca2+ transport through the solid electrolyte interphase (passivation layer formed at the interface between Ca anode and organic electrolyte), and thus the inefficient stripping/plating processes. Meanwhile, another challenge in this field concerns the development of Ca2+-storage electrode materials and in-depth understanding of the ingress process is required. Here, we introduce recent research progress on the electrochemical behavior of metallic Ca and its alloys in various electrolytes, as well as the intercalation (Prussian blue analogs, vanadium oxides, etc.) and conversion (Ca-sulfur batteries, Ca-oxygen batteries) cathode materials.